USPTO Patents Application 10004917

Application Serial No. 10/004,917 Page 3 of 7

Date March 18, 2004

Reply to Office Action dated December 30, 2003

Listing of the Claims:

1 . (Currently amended) A damper for provision in a hydraulic
clutch actuator system including betwe e n a master cylind e r cylinder, artd a slave
cylinder of th e system , and a damper between the master cylinder and the slave
cylinder, the damper including a housing, including port means for connecting in the
system and an imperforate diaphragm carried by the housing beneath the port means
and forming a boundary for the system so that the diaphragm may deflect in response
to vibrations transmitted through the hydraulic fluid in the system to effect damping of
the vibrations, characterized in that:

the housing has a canister configuration and includes a thin imperforate
annular sidewall above the diaphragm of substantially uniform thickness and coacting
with the diaphragm to define a large volume fluid chamber above the diaphragm
providing further system damping by virtue of vibratory volumetric expansion of the
annular sidewall.

2. (Original) A damper according to claim 1 wherein:

the housing includes an upper part defining the annular sidewall and the
port means and a lower part positioned beneath the diaphragm; and

the upper and lower parts coact to clamp a peripheral edge portion of
the diaphragm therebetween.

3 . (Currently amended) A damper according to claim 1 wherein:
A damper for provision in a hydraulic actuator system between a master cylinder and
a slave cylinder of the system, the damper including a housing, including port means
for connecting in the system and an imperforate diaphragm carried by the housing
beneath the port means and forming a boundary for the system so that the diaphragm
may deflect in response to vibrations transmitted through the hydraulic fluid in the
system to effect damping of the vibrations; characterized in that:

the housing has a canister configuration and includes a thin imperforate
annular sidewall above the diaphragm of substantially uniform thickness and coacting
with the diaphragm to define a large volume fluid chamber above the diaphragm
providing further system damping by virtue of vibratory volumetric expansion of the
annular sidewall;

the diaphragm comprises a an elastomeric diaphragm; and

Application Serial No. 10/004,917 Page 4 of 7

Date March 18, 2004

Reply to Office Action dated December 30, 2003

the damper further includes a stiff diaphragm carried by the housing
beneath the elastomeric diaphragm and forming a back up for the elastomeric
diaphragm.

4. (Original) A damper according to claim 3 wherein:

the housing includes an upper part defining the annular sidewall and the
port means and a lower part positioned beneath the stiff diaphragm; and

the upper and lower parts coact to clamp peripheral edge portions of
the elastomeric diaphragm and the stiff diaphragm therebetween.

5. (Original) A damper for provision in a hydraulic actuator
system between the master cylinder and a slave cylinder of the system, the damper
including a housing, including port means for connecting in the system and an
elastomeric diaphragm carried by the housing beneath the port means and forming a
boundary wall of the system so that the elastomeric diaphragm may deflect in
response to low frequency vibrations transmitted through the hydraulic fluid in the
system to effect damping of the low frequency vibrations and a further diaphragm
positioned beneath and generally parallel to the elastomeric diaphragm to form a gas
chamber therebetween and forming a back up for the elastomeric diaphragm so that
the elastomeric diaphragm may deform against the further diaphragm in response to
high frequency vibrations transmitted through the hydraulic fluid to cause deflection
of the further diaphragm to effect damping of the high frequency vibrations,
characterized in that:

the housing has a canister configuration and includes a thin imperforate
annular sidewall above the elastomeric sidewall of substantially uniform thickness and
coacting with the elastomeric diaphragm to define a large volume hydraulic chamber
above the elastomeric diaphragm providing further system damping by virtue of
vibratory volumetric expansion of the annular sidewall.

6. (Original) A damper according to claim 5 wherein the volume
of the hydraulic chamber substantially exceeds the volume of the gas chamber.

7. (Original) A damper according to claim 5 wherein the annular
sidewall forming the hydraulic chamber extends above the elastomeric diaphragm a
distance substantially exceeding the height of the gas chamber.

Application Serial No. 10/004,917 Page 5 of 7

Date March 18, 2004

Reply to Office Action dated December 30, 2003

8. (Original) A damper according to claim 2 wherein the annular
sidewall is configured above the elastomeric diaphragm to have a domed
configuration with the port means substantially at the apex of the dome.

9. (Original) A damper according to claim 5 wherein:
the further diaphragm comprises a spring steel diaphragm;
the housing is formed of a plastics material; and

the elastomeric diaphragm comprises a rubber diaphragm.

10. (Original) A damper according to claim 5 wherein the housing
comprises a two part housing including an upper part defining the annular sidewall
and coacting with the elastomeric diaphragm to define the hydraulic chamber and the
ports means and a lower part underlining the further diaphragm.

1 1 . (Original) A damper according to claim 10 wherein the upper
and lower parts define peripheral edge portions which coact to clamp peripheral edge
portions of the elastomeric diaphragm and the further diaphragm therebetween.

12. (Original) A damper according to claim 1 1 wherein the
peripheral edge portions of the upper and lower parts are held together in clamped
relation by an annular clamp band surrounding the peripheral edge portions of the
upper and lower parts.